Thomas allegedly told an acquaintance that she drowned her children in a bathtub and then left them under a neighbor’s home when she found burying them to be too difficult, Houston police spokesman Kese Smith told reporters.

The friend had come upon Thomas throwing out garbage in a vacant lot across from her Houston home, where she allegedly told him she needed immediate help moving.

When he asked where her kids were, Thomas allegedly told him she killed them, Smith said, according to CBS News.

“She was so matter of fact about it he didn't think she was serious. He thought she was joking," Smith said. "He continued to help her pack."

When she repeated that she had killed the children, the man drove Thomas to a nearby police precinct and flagged down an officer, officials said.

The children’s father is currently incarcerated and does not yet know what happened to his son and daughter, the man’s sister, Kita Thomas-Smith, told reporters.

Thomas-Smith took to social media to begin fundraising to give her niece and nephew a proper burial.

“Unfortunately we are trying to raise money for the going home services of our niece and nephew Kayana and Oraylan Thomas,” she wrote on GoFundMe, explaining that the children were “siblings who were murdered by the hands of their own Mother.”

A spokeswoman with the Texas Department of Family and Protective Services told InsideEdition.com that state child welfare officials had previously visited the family, but she could not disclose the nature of those visits. The Department of Child Safety is conducting an independent and comprehensive review of the family, she said.

Thomas also has a 12-year-old son, but he was not home at the time of the incident, the spokeswoman said. He will not be removed into CPS custody since he was with a relative at the time.